Electrical connectors



2, 1955 H. B. CRANE ELECTRICAL CONNECTORS Filed Jan. 15, 1954 INI/ENTOR.HOwqrcZB Crane ATTORNEYJ',

United States Patent ELECTRICAL CONNECTORS Howard B. Crane, Mamaroneck,N. Y.

Application January 13, 1954, Serial No. 403,743

3 Claims. (Cl. 339-74) The present invention relates to electricalconnectors and particularly to plug connectors for connecting appliances having terminal prongs to cords which are in turn connected toa power source.

At the present time many appliances such, for example,

flat irons, are provided with upstanding cylindrical prongs over which aplug comprising cylindrical sleeves is placed, the cylindrical sleevesof the. plug being connected to an electrical cord which is in turnplugged into the ordinary electrical outlet. Such plugs are retained onthe prongs of the appliance only by the friction of the sleeves.

Moreover, when such a plug is removed from the appliance the sleevesremain connected to the power source and the device is dangerous becausethese sleeves being thus connected may impart an electrical shock toanyone who handles the connector.

The present invention provides a plug connector having the parts thereofso organized that the frictional contact between the appliance prongsand the mating portions of the connector is exerted under springpressure and furthermore having the parts so arranged that when theconnector is removed from the appliance the openings in the housing,through which the prongs of the appliance extend, are closed and theuser cannot inadvertently come into contact with the contact elements.

It is an object of my invention to provide an electrical plug connectorwhich is resiliently retained in position on the prongs of the appliancewith which it is used.

It is another object of my invention to provide such a connector soorganized that upon removal of the connector from the prongs of anappliance the housing is closed and the electrically live portions ofthe connector sealed from the exterior thus eliminating all shockhazard.

It is another object of the invention to provide such an electricalconnector having few parts and being simply constructed and thereforeinexpensive to manufacture.

Other objects and features of the invention will be apparent when thefollowing description is considered in connection with the annexeddrawings, in which,

Figure 1 is a top plan view of the plug connector of my invention havinga portion of the outer housing broken away in order to show the positionof the internal parts;

Figure 2 is a longitudinal cross-sectional view of the device of Figure1, the section being taken on the plane of the line 22 of Figure 1;

Figure 3 is a transverse cross-sectional view of the electricalconnector, the view being taken on the plane of the line 3-3 of Figure1;

Figure 4 is a transverse cross-sectional view taken on the plane of theline 4* of Figure 1; and

Figure 5 is a perspective view illustrating the shape of the contactmember which in use makes contact with one of the appliance prongs.

Referring now to the drawings, there is shown at a housing member whichis generally rectangular in shape having one rounded end 11 and which isformed from electrically insulating material such for example asBakelite. The member 10 includes the upstanding rim portion ice 12 whichextends upwardly from base 13 on all sides thereof. Formed integrallywith the base 13 is an up standing transverse rib 14 having bores 15therein to receive the ends of screws 16. Contact members 17, such asshown in Figure 5, are formed with bent-off portions 18 which areprovided with openings 19 centrally thereof, these openings beingadapted to receive the threaded shanks of screws 16 to thus hold thecontact members 17 in place on the rib 14.

in order to ensure proper positioning of the contact members 17 alongitudinally extending rib 20 (Figs. 1, 2 and 4) is provided centrallyof the base 13 and adjacent the squared end 21 of the housing. The righthand ends of contact members 17, which are bent into semicylindricalform as shown at 41 (Fig. 5) fit between the outer rim l2 and the rib 20thus definitely determining the proper location of the contact members.

The contact members 17 and the heads of screws 16 are separated fromeach other at the ends 18 by means of a thickened portion 22 (Figs. 2and 3 of the upstandin g transverse rib 14. This barrier portion 22 alsoserves to separate the lead-in conductors 23 which have their endsstripped in the usual manner and placed under the heads of the screws 16as indicated in Figures 1 and 2.

The usual double conductor cord 24 comprising two conductors 23, asabove mentioned, is positioned in an opening 25 in the rim 12 at theleft end of the housing 10, this opening extending from the upper edgeof the rim to the base 13.

A cover member 26 is provided which cover member seats upon the rib orbarrier portion 22 and is fixed thereto by means of a screw 27. Thecover 236 has a thickened portion 28 located on the longitudinal centerline thereof which portion extends to the left as seen in Figures 1 and2 abutting against the barrier 22 at its right hand end and extendinginto the opening 25 at its left hand end. The cover thus serves to clampthe cord 24 in position against the base as well as to prevent contactwith the screws 16. Additionally, the cover 26 has a downwardlyextending portion 29 which overlies the offset of the contact member 17.

The housing is completed by means of a pivoted cover and gripping member30 which is pivoted to the side portions of the rim 12 by means ofscrews 31 which screws extend through the rim 12 and into threadedopenings in the sides of the cover member 30 or by means of a boltextending through a transverse bore provided therefor. The cover member30 is provided with a downwardly extending boss 32 beneath which thereis formed integrally with the base 13 a second boss 33. A coil spring 34seats around the bosses 32 and 33 and presses the cover and grippingmember 30 in a clockwise direction as seen in Figure 1. The right handends of the contact members 17 are bevelled as indicated at 35 in Figure5 thus making it possible for the member 3% to move to a position atwhich its right hand end lies against the base 13 closing the openings36 in the upstanding rim 12 and preventing access to the interior of thehousing 10. The rib 20 is also bevelled at its right hand end asindicated at 37, Figure 1, in order to permit the required clockwisemovement of the cover member 30.

It should be noted that member 30 has a sufficient thickness so thatwhen moved to its most clockwise position no gap is left at the lefthand end through which access could be had to the interior of thedevice. At the same time by simply depressing the left hand end of themember 30 against the pressure of the spring 34 prongs 38 of anappliance plug or the like designated 40 (and only a fragment of whichis shown in the drawings), may be inserted through the openings 36 andlie on and make contact with the semicylindrical ends 41 Patented Aug.2, 1955 of the contact members 17. Thereupon the release of the member30 will permit the spring 34 to urge the right hand end of member 30against the prongs 38 to hold them in position or more accurately tohold the entire plug connector in position on the prongs 38. Removal ofthe plug connector from the prongs will permit the spring 34 to urge themember 30 an additional amount in a clockwise direction closing theopenings 36 and preventing access to the interior of the plug connector,thus avoiding the shock hazard which is present in other devices of thissame general character.

While I have described a preferred embodiment of the invention, it willbe understood that I wish to be limited not by the foregoingdescription, but solely by the claims granted to me.

What is claimed is:

1, An electrical plug connector comprising, in combination, a housinghaving a cavity therein, a pair of longitudinally extending contactmembers spaced apart from each other in said cavity and adapted toreceive the prongs of an appliance plug, openings through said housinginto said cavity adjacent the ends of Said contact members, said ends ofsaid contact members adjacent said cavity openings being semicylindricalin crosssection and being bevelled to a point adjacent said cavity wallopenings, a cover for said cavity, means pivotally mounting said coverand means urging said cover to rotate to a position to close said cavitywall openings, said end then seating against the bevelled ends of saidContact members, said cover also serving to hold the prongs of anappliance plug against said contact members when said prongs areinserted through said cavity wall opening.

2. .In an electrical plug connector, in combination, a housing having acavity therein, a thickened rib extending transversely of said housingat one side of the transverse center line thereof, a pair of contactmembers extending longitudinally of said housing, each said contactmember having an upwardly offset portion lying on said thickened rib anda main longitudinally extending portion lying on the base of saidcavity, said main longitudinally extending portion being bent to form asubstantially semicylindrical surface, an upstanding longitudinallyextending rib lying between said main portions of said contact membersand spacing them apart, openings in said housing adjacent the terminalends of said contact members, a cover means for said cavity, means forpivotally mounting said cover means in the upper portion of said housingand resilient means for urging said cover means in a direction to closesaid openings when no plug prongs extend therethrough, said resilientmeans serving when plug prongs extend through said openings and lie inthe semicylindrical portions of said contact members to press said plugprongs into contact with said contact members, the ends of said contact5 members adjacent said housing openings being bevelled to permit saidcover member to close said openings when no plug prongs extendtherethrough.

3. In an electrical plug connector, in combination, a housing comprisinga generally rectangular base and integral upstanding walls, said housingbeing formed of electrically insulating material, a transverselyextending rib projecting upwardly from said base at one side of thetransverse center line thereof, a pair of contact members having oifsetportions resting on said rib and longitudinally extending portionsresting on said base at either side of the longitudinal center thereof,said contact members having upwardly curved sides bevelled near theextremities thereof an upstanding longitudinal rib formed integrallywith said base, said rib extending between said contact members andserving with said upstanding walls to position said contact members,means for fastening said contact members to said transversely extendingrib, said means also being adapted to fix cord conductors to saidcontact members, a slot extending from the top of the upstanding walldownwardly to the base at the end of said housing adjacent saidtransversely extending rib, said slot being adapted to receive aconductor cord, a thickened portion of said transversely extending ribbetween said contact members, a cover mounted on said thickened portion,said cover overlying said offset ends of said contact members andclosing one end of said housing, a downwardly extending central rib on.said cover, said rib lying adjacent the thickened central portion ofsaid transverse rib and extending into said conductor cord slot tothereby clamp said conductor cord in position against the base of saidslot, means for fastening said cover to said transversely extending rib,a main cover member extending from said first mentioned cover member tothe remote end of said housing, means pivotally mounting said main covermember in the upstand ing walls of said housing, the edge of said maincover member lying adjacent said first mentioned cover memher beingsufficiently thick so that no appreciable gap exists between said covermembers in any position of said main cover member, means urging saidmain cover member to rotate in a direction to press one end thereofagainst the base of said housing at the end remote from said transverserib', and openings in said housing adjacent the ends of said contactmembers, said openings being adapted to receive appliance plug prongs,said main cover member serving to press appliance plug prongs againstsaid contact members, and to close said openings when no applianceprongs extend therethrough by pressing downwardly against the saidbevelled ends of said contact members.

References Cited in the file of this patent UNlTED STATES PATENTS

